/*$$
 * Copyright (c) 1999, Trustees of the University of Chicago
 * All rights reserved.
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 * Redistribution and use in source and binary forms, with 
 * or without modification, are permitted provided that the following 
 * conditions are met:
 *
 *	 Redistributions of source code must retain the above copyright notice,
 *	 this list of conditions and the following disclaimer.
 *
 *	 Redistributions in binary form must reproduce the above copyright notice,
 *	 this list of conditions and the following disclaimer in the documentation
 *	 and/or other materials provided with the distribution.
 *
 * Neither the name of the University of Chicago nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
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package uchicago.src.collection;

/**
 * Replacement for objectspace's jgl pair class.
 *
 * @version $Revision: 1.3 $ $Date: 2004/11/03 19:51:00 $
 */

public class Pair {

  public Object first;
  public Object second;

  public Pair() {}

  public Pair(Object first, Object second) {
    this.first = first;
    this.second = second;
  }

  public boolean equals(Object obj) {
    if (obj == this) return true;
    if (obj instanceof Pair) {
      Pair other = (Pair)obj;
      return (other.first.equals(first) && other.second.equals(second));
    }

    return false;
  }

  public int hashCode() {
    int result = 17;
    result = 37 * result + first.hashCode();
    return 37 * result + second.hashCode();
  }
}
